The present invention relates generally to a security device and method which restricts motion of a transport device, and in particular to a security device and method that controllably restricts the vertical, axial rotation or pivoting of a swivel caster about a vertical pivot axis correlative to, inter alia, a user defined range of motion for restricting the path of the transport device to which the security device is attached, thereby securing the transport device such as a shopping cart, stroller or the like, in a restricted area.
Prior art devices for restricting the rotation of wheels attached to transport devices, such as carts, are known. These devices are especially well known in the retail industry where cart theft by customers and vagrants is prevalent and cart replacement by the retailer is costly. In this environment, it has been found that the prior art devices are plagued by a variety of problems. Foremost, the very nature of prior art devices mechanically locking up wheel rotation has been found to result in the destruction of the devices themselves and in the destruction of the associated wheels as a consequence of the cart being continually pushed or pulled long after the occurrence of mechanically locking up wheel rotation. Extreme occurrences of this type of destruction has been found to be prevalent with carts that have been collected after being wrongfully removed from a retailer""s premise and continually pushed or pulled long after the occurrence of mechanically locking up wheel rotation. The collection of carts, often in a train like structures, from the premise itself is also problematic in that some carts are continually pushed long after the occurrence of mechanically locking up wheel rotation thereby causing damage and ultimate destruction to the prior art devices and wheels.
Ultimately, customer service satisfaction suffers as a result of the customer having to deal with the laborious, time consuming, and costly maintenance associated with known prior art devices.
Additionally, known prior art devices have been known to abruptly lock up wheel rotation and thus, violently lock up the cart under normal customer use. This places the customer pushing the cart, a person in the cart and bystanders in harms way. And, at the very least, it has been found that customers abandon carts that abruptly locked up wheel rotation under normal customer use and walk out the retailer""s store thereby resulting in a lose of sales ultimately damaging the reputation of not only of the known prior art devices but the retailer""s reputation as well.
Moreover, the known prior art devices generally mechanically complicated and are prone to failure under the predations of certain weather conditions, such as snow slush, freezing and the like.
Thus, in general, know prior art devices do not provide systems which take into account, inter alia, wear on the device parts and the associated wheels, mechanical simplicity, and device failure in certain weather conditions such as snow, slush, freezing and the like.
For example, the patent to French, et al, teaches a security device for a shopping cart that includes a braking member rotatably mounted on a wheel axle of one of the wheels. The braking member is movable between a raised position spaced above the ground surface and an operative position contacting the ground surface, and has a portion projecting radially outwardly from the outer peripheral rim of the wheel at least in the operative position so as to lift the wheel from the ground and impede rotation of the wheel. A locking device releasably locks the braking member or shell in the raised position, and is released by a trigger device in response to a signal from a signal system extending around an area in which carts are to be retained, at which point the braking member rotates into the operative position. The device is activated by a buried perimeter loop antenna system which extends around a predesignated area in which the carts are to be retained, and is connected to a signal generator.
Hence, the device of French, et al, is, inter alia, mechanically complicated and is prone to failure under the predations of certain weather conditions, such as snow, slush, freezing and the like wherein, for example, the braking shell can freeze into a lock position or become jammed by snow and slush clogging the braking shell thereby preventing it from moving from a raised to a lowered position. Moreover, the buried perimeter loop antenna is expensive to install, requires that the perimeter of the predesignated area (i.e., the perimeters of a retail establishment""s parking lot) be torn open so the loop antenna can be installed and is easily defeated by the consumer by simply xe2x80x9csnippingxe2x80x9d or xe2x80x9ccuttingxe2x80x9d the loop antenna thereby deactivating the system.
The patent to Schweninger teaches a toggle brake assembly which can be automatically actuated by an audio frequency signal when a shopping cart is taken out of a designated area. When actuated, as the wheel rotates in either direction, the toggle wedges or hooks to brake the wheel. To unlock the brake, a special reset key must be inserted into the brake assembly and turned.
Hence, the assembly of Schweninger is, inter alia, prone to both wear on the assembly parts and the associated wheel and is also prone to failure under the predations of certain weather conditions, such as snow, slush, freezing and the like wherein, for example, the braking wedges can freeze into a lock position or become jammed by snow and slush thereby preventing the toggle wedges or hooks from braking the wheel.
The patent to Harris, et al, chronicles applicant""s efforts in the field of security devices for shopping carts. The patent to Harris et al, teaches a security device for a shopping cart utilizing a housing that is mounted to the cart in the vicinity of the wheel. A locking element supported to the housing and is selectively movable into positions engaging the cart wheel or being disengaged from the cart wheel. A motor is employed to move the element in such reciprocal motion and is operated by a controller. The controller includes a counter to determine the number of revolutions completed by the wheel, and a trigger for starting the motor upon receipt of a signal from the counter representing a preselected number of revolutions completed by the wheel.
Hence, the device of Harris, et al, is prone to both wear on the device parts and the associated wheel and is also prone to failure under the predations of certain weather conditions.
In light the foregoing, there is a need for a security device and method for transport d devices such as shopping carts, strollers or the like, that does not destroy itself nor destroy the wheel to which it is coupled under operating conditions. Additionally, there is a need for a security device and method that does not abruptly and violently lock up the transport device. Furthermore there is a need for a security device and method that is generally impervious to the predations of certain weather conditions and that substantially eliminates the problems associated with the mechanical complexities of know prior art devices.
Specifically, there is a need for a security device and method that can be repeatedly used to restrict carts to a restricted area while remaining undamaged. Additionally, there is a need for a security device and method that eliminates wheel lock up and the mechanical damages associated therewith. Furthermore, there is a need for a security device and method that eliminates the mechanical complexities associated with the known prior art devices thereby eliminating the expense unreliability and time consumption associated with maintaining these devices.
The present invention is distinguishable over the known prior art in a multiplicity of ways. For one thing, the present invention provides a security device and method that does not destroy itself nor destroy the wheel to which it is coupled under operating conditions thereby providing a security device and method that can be repeatedly used to restrict carts to a restricted area without damaging the associated wheel or the device itself. Additionally, the present invention provides a security device and method that does not abruptly and violently lock up the transport device. Furthermore, the present invention provides a security device and method that is generally impervious to the predations of certain weather conditions and that substantially eliminates the problems associated with the mechanical complexities of the know prior art devices thereby eliminating the unreliability of these devices, and the expense and time consumption associated with maintaining these devices. Moreover, the present invention provides a security device and method that eliminates the laborious, time consuming, and costly maintenance associated with known prior art devices thereby eliminating the associated customer service dissatisfaction.
Particularly, a transport device retention system is provided in the form of a security device and method that inhibits rotation or pivoting of a wheel of a transport device about a vertical pivot axis normal to the rotational axis of the wheel and fixes the wheel at an acute angle relative to the normal, forward or reverse direction of travel of the transport device. It should be noted that is was generally found that an acute angle of twenty-five degrees or greater resulted in the chance that the transport device, such as a shopping cart, would tip over on its side on lock up. When the acute angle was lowered to about twenty-one degrees shopping cart tip over was substantially eliminated. Thus, in the light of safety, the angle is preferably set below twenty-one degrees and in one preferred form the angle is about seventeen degrees, which causes a shopping cart to generally sweep a circle having approximately a ten-foot diameter.
The security device includes a housing unit comprised of a top cover and a bottom cover, a cup, collar or extension attached to a caster assembly comprised of a wheel cradled in and having an axle mounted to a forked frame, which is pivotally coupled to a mounting stud such that the forked frame and wheel can pivot about a vertical pivot axis, with the axle of the wheel (which defines an axis of rotation of the wheel) offset horizontally from the vertical pivot axis. This geometry provides a stable assembly in which the wheel axle will tend to trail the vertical pivot axis when a horizontal motive force is applied to the cart, the axle tending to align perpendicularly to the direction of motion of the cart.
The housing unit is attached to the frame of a transport device such as a cart by removing the existing caster and wheel and replacing it with the security device by passing the metal mounting stud through the housing unit and operatively coupling the stud to the frame of the cart. The housing unit also includes a locking element that is capable of moving into positions to inhibit wheel rotation or swivel about the vertical pivot axis and being disengaged such that wheel movement about the vertical pivot axis is no longer inhibited. The locking element is in one form of a pin that resides in a housing in the bottom cover and is capable of sliding into and out of notches strategically formed in the cup, collar or extension. Motor means are provided for moving the element back and forth through a lever that can be cam operated. When the element is activated by the motor, the moveable element is deployed and biased against the cup or securely received in one of the cup""s notches, fixing the wheel at an acute angle relative to the normal forward or reverse direction of the cart such that the cart can now only move in a circular direction. Thus, the locking element does not act as a xe2x80x9cbrakexe2x80x9d or xe2x80x9cstopxe2x80x9d for the cart wheel, rather it inhibits its direction of travel to a restricted circular path.
The present invention further includes a control system for activating the motor correlative to a user-defined value or event. The control system includes a transducer that outputs signals correlative to cart motion. The control system processes the output signals and compares the results to the user defined value or event which in accordance to one aspect of the present invention results in the control system being placed in a lockup mode wherein the motor is activated as delineated hereinabove and the moveable element is deployed and securely received in one of, for example, the cup""s notches or deployed and biased against the cup wherein when a certain angle of rotation of the wheel about the vertical pivot axis is achieved it causes the moveable element to be securely received in one of the cup""s notches for fixing the wheel at an acute angle relative to the normal forward or reverse direction of the cart such that the cart can now only move in a circular motion.
A receiver is also employed in the control system and operates in conjunction with one or more signal transmitters. By way of example, the receiver recognizes a code originating from one or more signal transmitters. The receiver, upon receipt of the signal from one or more transmitters, can produce a signal, through a decoder which is transferred to a microcomputer capable of functioning to, inter alia, ACTIVATE, DEACTIVATE, LOCKUP, and UNLOCK the device of the present invention. The transmitter receiver combination may be employed to function in a SET DISTANCE mode thereby determining the time or distance that the cart will be permitted to travel before the LOCKUP mode is triggered.
Accordingly, it is a primary object of the present invention to provide a new and novel security device and method for a swivel caster attachable to a transport device such as a shopping cart, stroller or the like.
It is a further object of the present invention to provide a device as characterized above which is capable of electronically determining the distance traveled by the transport device and triggering a locking element to inhibit the movement of a wheel about a vertical pivot axis such that the transport device to which the wheel is attached can only move in a circular direction.
It is a further object of the present invention to provide a device as characterized above which limits the distance of travel of a transport device to preclude the transport device from being removed from a predesignated area.
It is a further object of the present invention to provide a device as characterized above which is capable of restricting the directional path of the transport device upon receipt of a signal or after having traveled a preset distance or for a preset period of time.
It is a further object of the present invention to provide a device as characterized above which is capable of operating in multiple modes and may be manipulated remotely.
It is a further object of the present invention to provide a device as characterized above which is less susceptible to weather conditions than known prior art devices.
It is a further object of the present invention to provide a device as characterized above that is less susceptible to wheel wear than known prior art devices.
It is a further object of the present invention to provide a device as characterized above which is less susceptible to vandalism than known prior art devices.
It is a further object of the present invention to provide a device as characterized above which is capable of sounding an alarm within a preset perimeter.
It is a further object of the present invention to provide a device as characterized above that lends itself to mass production and is cost effective to manufacture.
It is a further object of the present invention to provide a device and method as characterized above for a shopping cart which is passive in nature to the consumer and unobtrusively locks up into a condition wherein the cart merely feels like it is not steering properly because the radius of the circle in which the cart is traversing is large compared to the relative area within a retail store or other like structure wherein when the cart is in an area such as a parking lot the radius of the circle in which the cart traverses easily secures the shopping cart in a restricted area.
These and other objects will be made manifest when considering the following detailed specification when taken in conjunction with the appended drawing figures.